Interface and widget specialist ETS has another handy solution available, this time for sending AES/EBU digital audio signals over long distances.
The PA850 series feature an XLR connector on end and an RJ-45 jack on another and are used to convert audio for distribution over Cat-5 cable (and select untwisted twisted pair wiring) up to 100 meters. Both male and female are available — PA850 is XLR male and PA851 is XLR female.
The adapters are isolated, balanced and impedance-matched for maintaining signal quality. Price: $74.